Meant to be Seen

So I have been mulling over doing a DIY HMD for a while, but now I think I am finally going to give it a shot. So far I have bought a few items to help me build a proof-of-concept, which you can see below:
- Magnifying Headset
- Pocket LED
- Credit Card Fresnel Lens x5
- Paper Anaglyph Glasses
- Galvanized Utility Wire
- Duct Tape
- Crazy Glue

I know it doesn't look like much, but you gotta start somewhere. What I am planning on doing is printing out some game screenshots onto photo paper, and using the utility wire to create a frame for the "screen". This will be mounted on the magnifying headset. I'll take the fresnel lenses and bend them in a "U" shape (concave facing user) and place them over each eye. I have already done a quick test with some bent fresnels and I think it will allow for high FOV. The fresnels I just got are a lot higher quality, and not as blurry as those older ones used in the video. If this works out for one eye, then I will do both eyes, but using a printing of an anaglyph 3D image from a game. Hopefully, this will be enough to see if the design is sound. Then the next steps will be making it real. The real unit is going to be based upon dual passive DLP pico projectors. I am aiming to complete the whole project for under $1,000. I will settle for no less than 180 degrees horizontal FOV. Yes, I am going all the way! I'll post some more designs and the progress of the project in the near future. Any feedback would be helpful.

That's the spirit!
I wish you the best of luck, and I will watch how project is going.

Good to see the Cyber weigh in on the "Craze"

Of note. I don't think you can use a Fresnel per eye to look at a singe screen if that is what you are testing with, they seem to bend the view so much it doesn't work out but your mileage may vary.

I have been very lax on my projects for ages so i hope you can inspire me to do more.

Wow, ambitious! I hope you are able to get this working!

Cool and interesting!

Okta wrote: I don't think you can use a Fresnel per eye to look at a singe screen if that is what you are testing with, they seem to bend the view so much it doesn't work out but your mileage may vary.

Well the screen itself will be curved, and have a projector for each eye. For the proof-of-concept I will be using anaglyph, but the views will not have 100% overlap. I will basically just be emulating what I could do with 2 projectors. I've done some tests with the fresnel just looking at my flat monitor, and it looks pretty good to me. I know that there will be a lot of distortion and blur, but I'm hoping enough of the image is in focus for it to be OK.

PalmerTech wrote:Wow, ambitious! I hope you are able to get this working!

Yes, I know. Thats why I'm doing this proof-of-concept before I spend any real money on equipment. Should know in the next couple weeks if this is worth pursuing. However the Vuzix 1200VR is coming out soon, so I will probably pick that up first before I spend money gambling on this DIY project. But I have high hopes of this DIY HMD.

"the views will not have 100% overlap."

How are you going to do that? Is somebody making a 3d driver that allows it now, or is it for custom software? Might be worth asking the iz3d people if they can add it to the driver, i'm pretty sure they added display mirroring when someone asked. (or did I imagine it?)

Anyway, good luck.

There's no need for software support. He's going for dual projection, so the overlap can be altered manually.

Hmmm, I thought he meant less than 100% overlap to get bigger fov. Maybe not?

bobv5 wrote:Hmmm, I thought he meant less than 100% overlap to get bigger fov. Maybe not?

You can't get 100% overlap for 180 degree FOV. Your own eyes have rather small overlap FOV.

Which means software support is needed!

bobv5 wrote:Which means software support is needed!

The software already supports this. That is what the "convergence" setting on IZ3D does. However, if you are using dual projection (like I am) you have the option of using far higher settings than would be comfortable on a normal monitor with 100% overlap.

Cyberreality, you might want to confirm in your testing, that a Fresnel, and especially a bent Fresnel, does not affect polarization in any unexpected way. I have no idea if it does, but it would be a shame to proceed and not know for sure. I imagine you can do this by putting a a pair of LEDs where your projectors would be and putting polarizers over them.

I've seen little toy LED projectors on sale. In the U.S., Toys-r-us has a few different ones for under $10, if you wanted to test out your ideas with them. They are not stereoscopic, of course, but a pair might be good for testing the polarization set-up.


Joe Dunfee

cybereality wrote: The software already supports this. That is what the "convergence" setting on IZ3D does. However, if you are using dual projection (like I am) you have the option of using far higher settings than would be comfortable on a normal monitor with 100% overlap.

Not sure about this. I tried a few months back, and remember that I could only get less than 100% overlap the wrong way. With for example the left image shifting to the right instead of left. Maybe the software has been changed, or maybe I was doing something dumb, but I did try both negative and positive convergence values, and really can't think what you hope to do that I didn't. (Apart from no stupid mistakes perhaps? )

From a post on a different forum about the same thing--
"Try to tweak convergence until you get very high convergence valies (try a positive convergence value)
This should do it but will have the effect of making the entire scene display in front of the screens so if you want to reduce eyestrain you will need a hmd that is capable of physically moving the screens to achieve a wider field of view and have proper convergence."
http://forum.iz3d.com/viewtopic.php?t=3 ... 5cb8b56fca" onclick="window.open(this.href);return false;


Edit-- I only tried with iz3d, perhaps other drivers handles this different?

@cadcoke5: I've tested a large-sized fresnel with my Zalman, and it works fine with polarized glasses. I think it will work.

@bobv5: You may be right actually. I just assumed it would work with IZ3D, didn't actually test it. Seems like a nice excuse to develop my own 3D driver. More realistically, I could still do this with a custom 3D application. I already have some open source code for doing stereoscopy in Ogre.

I really hope this works out so I can follow your example. That video you posted has too much distortion, though. I assume the final HMD will have less. Will this be both 2D and 3D capable? If I knew exactly what to do, I'd spend up to $3000 on building a 2D/3D HMD with 180 degree FOV and 1080p resolution and minimal distortion for extended use right now. Do you have any updates, Cyber? What could raising the price beyond $1000 do? Get better optics, better screens, a better helmet build?

I found this in related videos, don't know if it's useful at all.

Yeah, there is going to be a lot of distortion with the way I plan to do it. Less than in that video (that was just a quick test) but still significant. The idea is that the horizontal FOV would be increased in games, so that the sides would just be for peripheral awareness. That way detail was not needed. I haven't worked on this much at all. Hoping to finish reading the 'Garage Virtual Reality' book that PalmerTech recommended. I'll keep you guys updating on the progress.

Oh, so this will really only be playable for PC games with adjustable FOV, then.

Aphradonis wrote:Oh, so this will really only be playable for PC games with adjustable FOV, then.

Thats the idea. I still have a lot of testing to do.

Aphradonis wrote:I really hope this works out so I can follow your example. That video you posted has too much distortion, though. I assume the final HMD will have less. Will this be both 2D and 3D capable? If I knew exactly what to do, I'd spend up to $3000 on building a 2D/3D HMD with 180 degree FOV and 1080p resolution and minimal distortion for extended use right now. Do you have any updates, Cyber? What could raising the price beyond $1000 do? Get better optics, better screens, a better helmet build?

I found this in related videos, don't know if it's useful at all.

The edge distortion diminishes when you move your eye closer to the lens so with a little stretching you can get a very high FOV.

Okta wrote: The edge distortion diminishes when you move your eye closer to the lens so with a little stretching you can get a very high FOV.

Yes, and if the screen itself is also curved, then there is even less distortion.

What about if you do experiment using more than one lense for each eye? This technique is used in cameras but mostly to reduce colordistortion (abberation) but maybe you can use them to get the laws of nature more on your side.

@Likay: Thanks. I may look into that. Right now I am just trying to get through this book (Garage VR), which has a number of designs for DIY HMDs. I am hoping that will give me a little background into what I should be doing.

cybereality wrote:@cadcoke5: I've tested a large-sized fresnel with my Zalman, and it works fine with polarized glasses. I think it will work.

What lens did you use? A Kantek? Why did you stop using it? Were the grooves too distracting? I'm wondering if the Kantek LCD monitor lenses are the same as or better than the larger TV magnifier lenses.

I'm using a fresnel slipstream sent me. Not sure the brand. I don't use it all the time (just due to limited space on my desk) but I would like to try it more.